I work as a CNC programmer. We have five 5-axis routers with 2 work tables each at my workplace. We use them for plastic trimming and drilling. The machines aren’t the best in the market but they surely work for our purposes.

To cut the parts we place a thermoformed plastic on a holding fixture in the router. There are several parts that are similar to each with little difference like a cutout or the positions of some holes, so we may use a holding fixture for many different parts/programs.

This generates a lot of problems because sometimes the operators place the wrong fixture on the machine, or the correct fixture but the wrong program. This may cause a crash of the machine with the fixture and it can take up to 10 hours to fix it, depending on the severity of the accident and the skills of the maintenance technician who fixes it. This causes a production halt on the machine and it escalates the problem to other areas where they may need the parts that were about to be produced in order to keep working.

I noticed that Sparkfun sells FTDI breakouts in two configurations: 5V and 3.3V.

I have an old one and a new one, both 3.3V. One thing I noticed is that the new one had 3 solder points on the far side so I started investigating and realized that this is the voltage selector.

There are several reason why you would want to change the voltage, specially if you have two of them. For me, the reason was that my LCD screen is 5V and I didn’t want to alternate an external power source and the FTDI to upload the program and testing it.

Both look the same, difference is on the far side.

So, if you want to change the voltage of you FTDI breakout all you have to do is connect the solder points. If are seeing the board with the USB on to the left, connecting the top and the middle points provides 5V; on the same way, if you connect the bottom point with the middle you get 3.3V. Make sure you break the existing connection with a knife to avoid a short circuit.